1-WIRE ALTERNATOR
INSTALLATION INSTRUCTIONS
CAREFULLY READ THESE INSTRUCTIONS BEFORE ATTEMPTING ANY MODIFICATIONS!
Proper installation of this alternator is the responsibility of the installer. Improper modification or installation will void your warranty and may result in vehicle damage or personal injury. If you have any
installation questions, call our Tech Service personnel at 216-961-1800 from 7am to 4pm EDT.
One wire alternators eliminate the unsightly
factory wiring harness and simplifies installation by using only one wire for charging.
R (Left terminal)
R
INSTALLATION
To install a 1-wire alternator, disconnect the positive battery cable,
unbolt and remove the original alternator, install the new Tuff Stuff
1-wire alternator and re-tension the drive belts. Then simply run
one wire from the alternator ‘battery’ terminal to the positive terminal of the battery or to the starter solenoid main lug, which is connected to the positive battery post. Make sure that the battery
is fully charged. Reconnect the positive battery cable, start the
engine and using a VOM meter, verify that the alternator is charging at least 13.8 volts @ 1,000 engine RPM’s.
CORRECT WIRE SIZE IS CRITICAL
It is very important to use the correct wire size to connect the
alternator to the battery. A wire size too small can allow the wire to
overheat, melt the insulation and cause a fire or worse. Depending
upon the maximum output of the alternator, use the following chart
as a minimum wire size guide. Wire size is based on 4’ battery
cables. Trunk mounted batteries require heavier gauge battery
cables - contact Tech Service for recommendation.
Alternator Rating Wire Size
Simply connect one wire from the
positive battery terminal to the positive
alternator terminal. It’s that easy!
NO WARNING LIGHT
Note that a 1-wire alternator does NOT permit the use of a charge
warning (idiot) light. Most hot rodders and muscle car enthusiasts
prefer the use of a volt meter or ammeter to monitor charging.
However, certain Tuff Stuff alternators like the 7127, 7139 and
7140 series have terminals that may be used for a warning light.
To wire a warning light using one of these alternators, simply
remove the terminal plug cover and connect the R (Left terminal,
looking from the back of the alternator) to the warning light wire.
75 Amps
10 gauge
100 Amps
8 gauge
150 Amps
6 gauge
200 Amps
4 gauge
REQUIRES A GOOD GROUND
In order for an alternator to charge properly, an alternator must be
grounded to the engine block. If an alternator has paint or clearcoat on the mounting surfaces, it may not be grounded and will not
charge. For these reasons, many Tuff Stuff alternators include a
grounding tab that should be used to ground the alternator.
ROTATION SPEED
Alternators spin at approximately 2.5 times that of crankshaft RPM,
so an engine at a 700 RPM idle would spin the alternator at 1,750
RPM. Note that the maximum RPM of any Tuff Stuff alternator
should not exceed 15,000 RPM’s (6,000 engine RPM’s). There is
no need to worry about use of an underdrive pulley system or an
ignition regulator turn on with Tuff Stuff alternators. All Tuff Stuff alternators charge at very low engine RPM’s. No other manufacturer
in the industry has an alternator that produces more amps at low
RPM’s than Tuff Stuff.Also note that Tuff Stuff 1-wire alternators are
bi-directional and will charge when spun in either direction.
©2012 Tuff Stuff Performance Accessories, 9004 Madison Ave. Cleveland, Ohio 44102 www.tuffstuffperformance.com